1.31.2013

Ethos or Logos?

Last week, Bjorn Lomborg wrote an opinion piece in the WSJ preemptively attacking the climate policies that he speculates Obama will endorse. I don't usually read this kind of thing, but journalists at Climate Science Watch asked what I thought about it since they didn't believe it. Reading the article, I was surprised the WSJ had published it -- not because the citations were not 100% correct, but because the overall logic of the essay was flawed in obvious ways (regardless of your political stance). This is the kind of thing a copy-editor should have picked up on. My reply to the CSW mainly focused on this central logical flaw.

Interestingly, when CSW posted its reply to BL (here), which drew on many scientific experts, it was focused entirely on discrediting individual statements that BL had made

Displaying his trademark doublethink, Bjorn Lomborg’s latest op-ed in the Wall Street Journal switches between recognizing the risks of climate change and rejecting the need for meaningful action in the near term. Lomborg incorporates misleading and discredited scientific information to justify dangerous delays in climate action.

rather than pointing out that the giant "if-then" statement at the core of the article's architecture would obviously return an error if it were fed into any computer capable of boolean logic.

This struck me because the dialogue (in both directions) was focused on discrediting one's opponent, by demonstrating they don't understand science (BL does this to Obama, and CSW does this to BL), rather than finding a logical solution to the problem (or simply having a logical discussion about it). This seemed unfortunate, since in this particular case, the physical science is pretty irrelevant to the actual policy discussion. The entire discussion should be focused on the economics. I blame BL for inappropriately bringing the science into the discussion, but I wish CSW had pointed out that that was the error, since I think doing so (here and elsewhere) would get us back on track to meaningful discussion rather than escalating the scientific mudslinging.

My fully reply to the CSW is below the fold (I had been in referee-mode at the time, which is probably evident).

Here are a few comments that I jotted down very quickly. A fully crafted response is a bit difficult because the article isn't very logical in its structure, so its easier to just point out things that don't make much sense. Some of the points relate to my experience with climate-economics, but most of my comments are actually just pointing out that BL isn't really making sense in his basic logic.

In his second inaugural address on Monday, President Obama laudably promised to "respond to the threat of climate change." Unfortunately, when the president described the urgent nature of the threat—the "devastating impact of raging fires, and crippling drought, and more powerful storms"—the scary examples suggested that he is contemplating poor policies that don't point to any real, let alone smart, solutions.

I don't see how these "scary examples suggest" anything about the type of policies that Obama is contemplating. They are just examples of climate impacts and they say nothing about the policy tools he plans to use.

It seems like BL would like to discuss policy instruments, but tries to get to that discussion point by accusing Obama of exaggerating distracting climate impacts. This is ironic, since BL is linking two unrelated issues -- which is distracting.

Historical analysis of wildfires around the world shows that since 1950 their numbers have decreased globally by 15%. Estimates published in the Proceedings of the National Academy of Sciences show that even with global warming proceeding uninterrupted, the level of wildfires will continue to decline until around midcentury and won't resume on the level of 1950—the worst for fire—before the end of the century.

BL is not citing his sources well enough that anyone can check his work. A google scholar search of "PNAS, wild fires and climate change" returns >1500 articles, so I don't know what's behind these numbers.

However, the point about changes since 1950 is a red herring, since events that have happened since 1950 are irrelevant to whether future warming will cause more wild fires and what the social cost will be. Climate change impacts over the next 60 yrs are expected to be much larger than anything observed in the last 60 yrs.

Claiming that droughts are a consequence of global warming is also wrong. The world has not seen a general increase in drought. A study published in Nature in November shows globally that "there has been little change in drought over the past 60 years." The U.N. Climate Panel in 2012 concluded: "Some regions of the world have experienced more intense and longer droughts, in particular in southern Europe and West Africa, but in some regions droughts have become less frequent, less intense, or shorter, for example, in central North America and northwestern Australia."

The logic of this paragraph is faulty in multiple ways. First, BL makes the same error about using the trend over the last 60 years to infer something about the future (see above). Second, the quote from the UN does not in any way support BL's statement that "Claiming that droughts are a consequence of global warming is wrong". Regardless of whether the two quotes in the paragraph are true or not, there is nothing in the paragraph that would support this claim by BL (assuming it is true).

As for one of the favorites of alarmism, hurricanes in recent years don't indicate that storms are getting worse. Measured by total energy (Accumulated Cyclone Energy), hurricane activity is at a low not encountered since the 1970s. The U.S. is currently experiencing the longest absence of severe landfall hurricanes in over a century—the last Category 3 or stronger storm was Wilma, more than seven years ago.While it is likely that we will see somewhat stronger (but fewer) storms as climate change continues, a March 2012 Nature study shows that the global damage cost from hurricanes will go to 0.02% of gross domestic product annually in 2100 from 0.04% today—a drop of 50%, despite global warming.

I actually do know which study BL is citing here, since hurricanes are my specialty (the Mendelsohn et al. paper actually was published in January, not March).

The quote is misleading in suggesting that costs will "drop". Mendelsohn et al. estimate that direct damages will more than double from $26B per year to $56B per year by 2100 (the USA and China are projected to each lose $25B and $15B per year, respectively). The decline as a fraction of GDP is driven entirely by GDP growth, and not because damages decline.

There are multiple reasons why these numbers should not be settling. First, these estimated costs as a fraction of GDP (from Mendelsohn et al) are much larger in poorer countries, such as the Caribbean and Central America, where these direct damages are expected to rise by as much as 0.25% of GDP (due to climate change). Second, the direct destruction of infrastructure is not the only cost of hurricanes. A growing body of work is showing that the true cost is much larger. For example, Tatyana Deryugina of University of Illinois has shown that federal transfers (such as unemployment insurance) may be around ten times larger in total cost than these direct damages (paper here). Similarly, in a paper of mine with Jesse Anttila-Hughes of University of San Francisco, we show that lost income is roughly fifteen times larger than direct damages in the Philippines, which is one of the most intense hurricane environments in the world. In general, the more we look at this issue (and researchers haven't been looking at it very long) the more we realize that the total losses to these events are much larger than we previously thought. So the estimates from Mendelsohn et al should be seen as a lower bound. If we were to scale them up by a factor of ten, following these other recent papers (so for the USA, it would be something around $250B), then we would probably start to worry more.

This does not mean that climate change isn't an issue. It means that exaggerating the threat concentrates resources in the wrong areas.

This is where BL again makes a large logical leap (which I cannot follow). Whether or not you agree that Obama is "exaggerating" these threats, discussing them does not "concentrate resources" anywhere.

Consider hurricanes (though similar points hold for wildfire and drought). If the aim is to reduce storm damage, then first focus on resilience—better building codes and better enforcement of those codes. Ending subsidies for hurricane insurance to discourage building in vulnerable zones would also help, as would investing in better infrastructure (from stronger levees to higher-capacity sewers).These solutions are quick and comparatively cheap. Most important, they would diminish future hurricane damage, whether climate-induced or not. Had New York and New Jersey focused resources on building sea walls and adding storm doors to the subway system and making simple fixes like porous pavements, Hurricane Sandy would have caused much less damage.

It is true that investing in protection is good policy idea, but it may not be as cheap as BL thinks. Daiju Narita of the Kiel Institute for the World Economy and I have recently published a paper studying how well we can protect ourselves from hurricanes. We have gotten better at protection over time, but it is still quite expensive and we see that even in the most heavily protected countries (eg. Japan) that there are substantial losses to storms.

The rest of this article discusses real economic issues, but they are unrelated to the President's quoted statements and they are not more or less true depending on whether we believe that the president was exaggerating or not.

In the long run, the world needs to cut carbon dioxide because it causes global warming. But if the main effort to cut emissions is through subsidies for chic renewables like wind and solar power, virtually no good will be achieved—at very high cost. The cost of climate policies just for the European Union—intended to reduce emissions by 2020 to 20% below 1990 levels—are estimated at about $250 billion annually. And the benefits, when estimated using a standard climate model, will reduce temperature only by an immeasurable one-tenth of a degree Fahrenheit by the end of the century.

Even in 2035, with the most optimistic scenario, the International Energy Agency estimates that just 2.4% of the world's energy will come from wind and only 1% from solar. As is the case today, almost 80% will still come from fossil fuels. As long as green energy is more expensive than fossil fuels, growing consumer markets like those in China and India will continue to use them, despite what well-meaning but broke Westerners try to do.

Instead of pouring money into subsidies and direct production support of existing, inefficient green energy, President Obama should focus on dramatically ramping up investments into the research and development of green energy. Put another way, it is the difference between supporting an inexpensive researcher who will discover more efficient, future solar panels—and supporting a Solyndra at great expense to produce lots of inefficient, present-technology solar panels.

When innovation eventually makes green energy cheaper, everyone will implement it, including the Chinese. Such a policy would likely do 500 times more good per dollar invested than current subsidy schemes. But first let's drop the fear-mongering exaggeration—and then focus on innovation.